12.—(1) The Department may review any certificate of recoverable benefits if it is satisfied—
(a)that the certificate was issued in ignorance of, or was based on a mistake as to, a material fact, or
(b)that a mistake (whether in computation or otherwise) has occurred in the preparation of the certificate.
(2) On a review under this Article the Department may either—
(a)confirm the certificate, or
(b)(subject to paragraph (3)) issue a fresh certificate containing such variations as it considers appropriate.
(3) The Department may not vary the certificate so as to increase the total amount of the recoverable benefits unless it appears to the Department that the variation is required as a result of the person who applied for the certificate supplying the Department with incorrect or insufficient information.